I am a new beek this year, with four hives: 2 packages split when re-queened. I have read what I can find on varroa, drone frames, and life cycle of the varroa in the cell. I am asking if my understanding of the varroa count is correct.
I have used green drone frames in 8 frame medium bodies with SBB since June. I have switched them out when they have a sufficient number of capped drones, and frozen/replaced them. Approximately every three weeks, less often in the splits from the original packages. In checking for varroa in July, I found none in 50 capped cells/per frame that I opened, almost all of which were pink/purple/slightly pigmented stage. I now have one varroa per 50 capped cells. I don't see this at the treatment threshold, but know the level is increasing.
Should I be looking at different stages of drone pupae? The two rust colored varroa that I observed were not moving; does this signify daughter varroa, and not the mother? Am I correct in thinking that there probably won't be immature (less visible) stages of varroa in the cell if I don't see an adult? I pulled all the drone frames yesterday, in the start of downsizing the hives for fall. Should they have been left in until much colder weather?